void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  pinMode(4, INPUT_PULLUP);
}

void loop() {
  int a=digitalRead(4);
  Serial.println(a);
  if(a==HIGH){
Serial.println("Motion Detected");
  }
  if(a==LOW){
Serial.println("Motion not Detected");
  }
 delay(10);
}